Nozzle for metallurgical equipment



Oct. 28, E E SUCK NOZZLE FOR METALLURGICAL EQUIPMENT Filed June 5, 1948zig. l

Brwentor Edwin E .Slz'c un B Ctiornegs Patented @et 28, 1952 UNITEDSTATES PATENT? NozzLs Fon MTALLURGICAL Eomrivisin:'gr

Edwin E. slick, Pittsburgh, ra. l Application June 5, 194s, serial No.cisco I n 2 Claims. (oi. 22-85 This invention relates to nozzles of thetype used in metallurgical equipment such as ladles and the like,through which molten metal is discharged from the bottom of thereceptacle.

Nozzles of the kind to which the present invention pertain are commonlyprovided in the bottom of metallurgical ladies and other equipment intowhich molten metal is charged. The ladle or other equipment is commonlyprovided with a vertically movable plug or stopper that is raised andlowered over the upper end of the nozzle for controlling the dischargeof molten metal therethrough.

Considerable difficulty is sometimes encountered during a pour inoperating the plug to close ofi the flow of metal at the proper time.This is occasioned by failure of the plug to conform tothe seat providedfor it in the upper end of the nozzle. It'has heretofore been proposedto remedy this condition by forming the nozzle in two separate parts,one of which is designed to provide a better seat for the plug, butthese generally have not been satisfactory, due principally'to the costand difficulty of making them, and due to the separation of the partswhich occurred in their use.

The present invention has for its object to overcome this vdifficulty byproviding `a single piece nozzle in which the upper seat-forming end isof slightly softer character at operating temperatures than theremainder oi the nozzle. This softer part, when exposed to the moltenmetal in the ladle, will yield and conform to the plug when the plug isforced down against it to thereby cut ofi the flow of metal through thenozzle.

My invention may be more fully understood by reference to theaccompanying drawing, which illustrates a vertical section through anozzle constructed in accordance with my invention, and wherein thecooperating plug is indicated in dotted lines.

in the drawing, 2 designates a single-piece nozzle, and 3 shows thelower portion of the plug in dotted lines, the plug being shown seatedon top of the nozzle or spout. The associated parts of the ladle orother metallurgical apparatus in which the nozzle is used are notillustrated, these being of conventional form.

The nozzle 2 is normally provided with a tapered lower end, and with apassageway l eX- tending axially throughout its length. At the upper endof the body the passageway 4 flares outwardly providing a seatingsurface Ei.

The single piece body E has the rst few inches of the upper portionformed. ofrefractoryl which is softer under operating conditions thanthe remaining part of the nozzle. This condition may be brought about invarious lways. The'wnozzles are usually formed of clay, and the upperpart y uof the body, infthe region. designated 5,; including the part-th'at carries the seat 5, i's.formed of a clay that hasr a slightlylower softeningtemperature or meltinglpoint'. For example [the main bodyof the nozzle 2 may soften ata temperature of around S000 F., whiletheitop :clay will soften at around 2700 Fan The Viigures'fhere givenare only by way of example, and the difference may be selected to agreaterA 0r lesser extent as the user may desire. Refractory clays,having such differences in softening' points, are well known in the art.f j 1 The nozzle is formed in this' caseiny arnold as is the usualpractice, by nrst` formrlgthe bodyy 2 fromthe hard clay and'then theupper part or" the moldisicharged with the .softe'rvclay to form theportion 6j The two bodies of clay bond togetherin the forming operation,`and constitute an integral one-piece body when the entire nozzle isfired. y f 4 In lieu of using clay of two different kinds, clay ofthesarnekind may be used but Laiilux may vbe lincorporated into the`,clay,.constit`uting the upper part 6 of the body, in which case thesame result is obtained.

Also, the body may be formed in one piece from a clay of uniformcomposition throughout. It is red in the usual way. Then the body isplaced with the upper end down, in a Vessel containing a solution of asalt or other compound to a depth of a few inches. The depth of thesolution depends upon the vertical height of the part 6 of the nozzle.The solution will be soaked into the part of the nozzle which isimmersed in it. After the body has stood in the solution for a desiredlength of time, preferably for at least several hours, it is taken outand allowed to dry. Upon evaporation of moisture, the salt compoundwhich was in the solution will be distributed in situ throughout theimmersed portion of the nozzle.

The compound which is employed in solution is one which will act as a uXto cause the clay upon being heated to soften below the temperature atwhich the remainder of the body will soften or cause it to bloat Variouscompounds may be used for this purpose, but common salt (NaCl) is quitesatisfactory and economical. Another compound of the same characterwhich may be used in solution is soda ash. These are 3 merely typical ofvarious compounds that may be employed, and which are well known toceramic engineers, and which will function to make the clay in the upperend of the nozzle softer under the conditions of use of the nozzle thanthe remaining part of the nozzle.

The softer material provides in effect a valve seat which will easilyaccommodate itself under the conditions of use to the seating of thevalve or plug- 3'. The remainder of the body' however, being harder,will more effectively resist erosion. Hence my invention provides apouring nozzle for ladles or the like formed of one piece and having theupper end of a refractory which is softer under conditions of use in theladle than the remaining part of the nozzle. Being in one piece, thenozzle has good mechanical strength, and is simple to manufacture. Byforming the nozzle entirely of one body of clay of uniform softeningpoint, firing it and then impregnating it with a flux, the nozzle isespecially strong and cheap t'o manufacture, in that it is unnecessaryduring the' manufacture or molding' the nozzle to change from one typeof clay to another. Also the' body is stronger because it is fired"before the fiuxing compound is impregnated into it, and hence the entirebody is fired to the same extent when the article is burned in the kiln,and there is' less likelihood of damage to the nozzle in being fired.

If the entire body were formed of the softer clay, it would erode' morerapidly, and more of the clay would be' carried away by the metal being'poured. Any clay so carried away contaminat'es the metal. By having a`one-piece nozzle in which only the upper part is of the softer material,the amount of the softer clay which contacts the molten metal isrelatively little and the contamination is only a small percentage ofthat which would occur if the entire nozzle were made of the softerclay.

While I have shown and described one specific form of nozzle, it will beunderstoodthat my invention is applicable to nozzles of different formsand shapes.

I claim:

1. The method of making a nozzle o'rmetaI- lurgical` apparatus, whichvnozzle comprises a onepiece refractory body having a central openingtherethrough and having a seat portion at the top thereof around saidcentral opening, which comprises shaping the body from a refractory massof uniform composition, firing the body, immersing the upper end of saidbody only in a solution carrying a fluxing compound, and removing thebody from the solution and evaporating the solvent whereby to deposit inthe immersed portion of the body the flux.

2. A nozzle for metallurgical apparatus comprising a one-piece bodyhaving an axial opening therethrough and a seat-forming portion forcooperationl with a valve plug at its upper end which is softer at thetemperatures and under the conditions in which the nozzle is used than lthe remaining portion of the body, said body be- ".,ing a firedrefractory clay body of uniform composition throughout and having itssaid upper end impregnated with a iluxing salt by immersing. said' upperend only in a solution of the salt to thereby lower the softeningtemperature of said' upper end as compared to said lower end.

EDWIN E. SLICK.

REFERENCES4 CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS OTHER REFERENCES Page 155, The Iron Age, July 19,1928.

